This relates generally to codecs or video encoders and decoders.
A video encoder compresses video information so that more information can be sent over a given bandwidth. The compressed signal may then be transmitted to a receiver that decodes or decompresses the signal prior to display.
Conventional video encoding algorithms result in losses. That is, in the course of compressing the video information, some information may be lost, resulting in decreased picture quality. Ideally, the video quality is improved to the greatest possible extent and the compression is increased to the greatest possible extent. However, these two goals tend to conflict with one another.